For the 10th year in a row, Microsoft chairman Bill Gates is the world's richest man.

Mr. Gates topped Forbes magazine's annual list of world billionaires this year, with a personal fortune of over $46 billion.

U.S. investor Warren Buffett stands second with nearly $43 billion, adding more than $12 billion to his net worth. German supermarket magnate Karl Albrecht is third with $23 billion, while Saudi Arabia's Prince Alwaleed bin Talal is fourth with just over $21 billion.

Forbes says there are 587 billionaires worldwide, up from 476 in 2003. Combined, the billionaires are worth nearly $2 trillion.

The list saw the addition of 64 new billionaires. Among the new rich is the author of the Harry Potter series of children's books, JK Rowling, and the two creators of the popular Internet search engine, Google - Sergey Brin and Larry Page.